Multipurpose Internet Mail Extension
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... Freed, N. and N. Borenstein, "Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies", RFC 2045draft ...
... Freed, N. and N. Borenstein, "Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types", RFC 2046draft ...
... Moore, K., "Multipurpose Internet Mail Extensions (MIME) Part Three: Representation of Non-Ascii Text in Internet Message ...